林生地霉与白念珠菌对小鼠大脑组织的致病性

Experimental Study on the Pathogenicity of Geotrichum Sivicola and Candida Albicans in Brain Tissue of Mice

目的探讨机体免疫状态及感染途径对林生地霉及白念珠菌系统感染的影响,研究林生地霉与白念珠菌对脑组织致病力方面有无差别。方法采用动物实验的方法,通过不同给药途径,给不同免疫状态下的昆明小鼠分别注射林生地霉及白念珠菌,观察实验小鼠的死亡率、平均存活天数、脑组织的真菌逆培养阳性率、真菌负荷量及组织病理学改变。结果接种不同菌种的免疫抑制腹腔组及免疫抑制静脉组小鼠的死亡率及平均存活天数与其它组比较,差异均有统计学意义(P均<0.05),免疫抑制皮下组逆培养阳性率明显低于免疫抑制腹腔组及免疫抑制静脉组,差异有统计学意义(P<0.05)。接种白念珠菌的各组小鼠脑组织真菌负荷量比较,差异有统计学意义(P<0.05)。接种白念珠菌小鼠脑组织PAS染色中可见到紫红色菌丝。结论林生地霉与白念珠菌一样,其致病力与机体免疫状态及接种途径密切相关。当机体免疫力下降时,白念珠菌可通过血脑屏障,而林生地霉则不能。

Objective To study the pathogenic difference between Candida albicans and Geotrichum sivicola in brain tissue of mice and explored their impact factors of different immune status and the route of infec- tion. Methods The mice were injected C. a/b/cans and G. sivicola respectively under different immune sta- tus with the different injection methods. The difference of mortality, average survival time, positive rate of the brain tissues inverse fungi culture, the fungi loading dose and the histopathological manifestations were ob- served. Results The death rate and mean survival time of the immunosuppressed group mice had significant difference（P 〈 O. 05 ） between the group of intraperitoneal injection and that of intravenous injection. The in- verse culture positive rate of immunosuppressed subcutaneous mice was lower than that in group immunosup- pression celiac and immunosuppression vein group （ P 〈 0.05 ）. The fungus loading dose was significant difference （ P 〈 0.05 ） between each group of mice brain tissues inoculated C. albicans. Some purple hyphae were observed in brain tissue inoculated C. albicans with PAS staining. Conclusion Both G. sivicola and C. albicans＇ pathogenicity were closely correlated with the body＇s immune status and vaccination approach. Candida alb/cans can go through the blood brain barrier.but Geotrichum sivicola can not.